Jellyfish Facts

They are umbrella shaped, clear sea creatures with long trailing tentacles. They move slowly through the water by pulsing the upper body. Also carried by ocean currents. Their tentacles can be 10 feet or longer.

Other Names. Jellies or sea jellies. Large groups of jellies are called a bloom. Blooms can close beaches.

Where They Live.Found in every ocean and coastline.

Numbers. Jellies have increased in numbers worldwide. Warmer ocean temps and pollution of ocean waters are factors. Fishing the ocean too much is also a cause. Tuna, shark and swordfish eat jellies.

Stings.Stings can occur while wading, swimming or diving in salt water. Honolulu gets over 1000 911 calls per month for stings.

Beached Jellies.Even beached or dying jellies can sting. So can pieces of tentacles floating in the water. They can release venom for up to 2 weeks.

Treatment. Vinegar is used to stop the venom in stingers. Caution: Do not use ammonia, urine, rubbing alcohol, fresh water or ice. They all can trigger the release of more venom. If you don't have vinegar, move on to scraping off the stingers.

Prevention.Mainly do not go in the water where jellies are seen. Wearing a thin layer of clothing (such as pantyhose) also can protect you. Reason: The stingers are short and cannot puncture clothing. Special "stinger suits" can be bought in diving stores.

Cause of Sting Reactions

The long tentacles have thousands of stingers.

When a stinger is touched, it pierces the skin and injects venom.

The venom is what causes all the symptoms.

Types of Jellyfish Sting Reactions

Local Reactions are most common. Symptoms are raised, red lines that cross each other. The sting causes pain or burning at the site. Sometimes hives in the sting area occur. Blisters can occur in severe cases. Severe pain lasts 1-2 hours. Itch may last for a week. If the skin damage is severe, red or purple lines can last for weeks.

General Reactions can occur if there are many stings. More stings give a higher dose of venom. Large venom symptoms are vomiting, dizziness, weakness and headache.

Anaphylaxis (A severe allergic reaction). Life-threatening reactions are very rare with the stings. Most are caused by box jellyfish found in the South Pacific and Australia. The main symptoms are trouble breathing and swallowing, along with hives. It starts rapidly, most often within 20 minutes of the sting.